Field of the Invention
This invention relates to a device for attaching a memory instrumentally for stitch control signal to a computerized sewing machine.
In some of the computerized sewing machines, the memory instrumentalities are produced in a cassette type. That is to say, for patterns of high frequency in use, electronic memory instrumentalities are housed within the sewing machine, while for patterns of low frequency in use, electronic memory instrumentalities are prepared in the cassette type for attaching to the sewing machine.
Unfortunately, in such sewing machines, orders of making and breaking of connecting pins between the cassette and a circuit of a computer are restrained when the cassette type memory instrumentalities are attached to and detached from the machine body because an earthing line is at first connected and broken at last, and on the other hand a control line of a power source is at last connected and at first broken.
If these lines are connected at the same time, and broken at the same time, there arises no problem. However, it is difficult to make such a structure.
Removal of the cassette type memory instrumentalities during the rotation of the sewing machine often causes reckless driving in the computer. With respect to the above mentioned restraining, the length of the connecting pin is designed so as to provide a proper connecting order.
For the problem caused by removing the cassette during the rotation of the sewing machine, operating manuals instruct handling of the cassette after breaking the power source, but notwithstanding errors will be made, and besides the operation of the cassette is troublesome.